It is preferable that a label indicating a name of various objects included in a video is added to the video. For example, if the above-described label is attached to a television program image, a broadcast station may search desired images if necessary from among many television program images. However, manually attaching the labels to the video takes huge amount of time and effort.
In recent years, a technique for automatically recognizing the name of the object included in the image has been studied. For example, there is a technique disclosed in T. Malisiewicz and A. A. Efros, “Recognition by association via learning per-exemplar distances”, Proceedings of the IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR), 2008, p. 1-8. If it is possible to automate the operation for adding labels to videos by using the above-described technique, the operation for adding the labels is efficient.
On the other hand, a technique for adding additional information to the video according to the content of the video has been proposed. For example, there is a technique for adding the program information related to each program broadcasted by digital broadcast and the genre of the program to the video. Furthermore, for example, there is a technique for extracting a frame in which the telop character is displayed from the image and recognizing the telop character. With reference to the database in which the font of the character corresponds to the image type, the technique determines the image type corresponding to the font of the recognized telop character. The above-described techniques are disclosed in, for example, Japanese Laid-open Patent Publication No. 2003-134412 and Japanese Laid-open Patent Publication No. 2006-53802.